Skip to main content Module state Copy item path Source ActiveTurn An in-progress turn — the assistant is actively streaming. AgentCapabilities Static capabilities an {@link AgentInfo} advertises. Modelled after MCP
capabilities: each field is opt-in and its presence (an empty object {})
signals support, while absence means the feature is unsupported and the
corresponding client commands MUST NOT be used. Sub-fields carry
per-capability options. AgentCustomization A custom agent contributed by a plugin or directory. AgentInfo AgentSelection A selected custom agent for a session. AhpMcpUiHostCapabilities The subset of MCP App
HostCapabilitieshostCapabilities of the ui/initialize response
delivered to an MCP App View. Annotation A conversation anchored to a specific file produced by a specific turn,
optionally narrowed to a range within that file. AnnotationEntry A single entry within an {@link Annotation}. AnnotationsState Full state for a session’s annotations channel, returned when a client
subscribes to an ahp-session:/<uuid>/annotations URI. AnnotationsSummary Lightweight per-session summary of the annotations channel, surfaced on
{@link SessionSummary.annotations} so badge UI can render annotation /
entry counts without subscribing to the channel itself. ChangesSummary Aggregate counts describing the file changes associated with a session. Changeset Catalogue entry describing one changeset the server can produce for a
session. ChangesetFile One file entry within a {@link ChangesetState}. ChangesetOperation A server-declared invokable verb the client can run against a
changeset, a file, or a range — "stage", "revert", "create-pr",
and so on. ChangesetState Full state for a single changeset, returned when a client subscribes to
an expanded changeset URI. ChatInputAnswered ChatInputBooleanAnswerValue ChatInputBooleanQuestion Boolean question within a chat input request. ChatInputMultiSelectQuestion Multi-select question within a chat input request. ChatInputNumberAnswerValue ChatInputNumberQuestion Numeric question within a chat input request. ChatInputOption A choice in a select-style question. ChatInputRequest A live request for user input. ChatInputSelectedAnswerValue ChatInputSelectedManyAnswerValue ChatInputSingleSelectQuestion Single-select question within a chat input request. ChatInputSkipped ChatInputTextAnswerValue Value captured for one answer. ChatInputTextQuestion Text question within a chat input request. ChatState Full state for a single chat, loaded when a client subscribes to the chat’s
URI. ChatSummary Lightweight catalog entry for a chat, carried in
{@link SessionState.chats | SessionState.chats}. The full conversation
lives in {@link ChatState}, which inlines (denormalizes) every field below. ClientPluginCustomization A {@link PluginCustomization} as published by a client. Extends the
server-facing shape with an opaque nonce so the host can detect when
the client’s view of a plugin has changed and re-parse only as needed. ConfigPropertySchema A JSON Schema-compatible property descriptor with display extensions. ConfigSchema A JSON Schema object describing available configuration properties. ConfirmationOption A confirmation option that the server offers for a tool call awaiting
approval. Allows richer choices beyond simple approve/deny — for example,
“Approve in this Session” or “Deny with reason.” ContentRef A reference to large content stored outside the state tree. CustomizationDegradedState Container partially loaded but has warnings. CustomizationErrorState Container failed to load. CustomizationLoadedState Container loaded successfully. CustomizationLoadingState Container is being loaded by the host. DirectoryCustomization A directory the host watches for this session. ErrorInfo FileEdit Describes a file modification with before/after state and diff metadata. HookCustomization A hook manifest contributed by a plugin or directory. Icon An optionally-sized icon that can be displayed in a user interface. InputRequestResponsePart A resolved input request (elicitation) recorded in the turn transcript. MarkdownResponsePart McpServerAuthRequiredState Server is reachable but cannot serve requests until the client
authenticates. Mirrors the discovery flow defined by
RFC 9728
(Protected Resource Metadata) and the OAuth 2.1 / RFC 6750 challenge
semantics required by the MCP authorization spec. McpServerCustomization An MCP server contributed by a plugin or directory. McpServerCustomizationApps Information from the agent host needed to render MCP Apps served
by this MCP server. McpServerErrorState Server failed to start, crashed, or otherwise transitioned to a
non-recoverable error. Use {@link McpServerStatus.AuthRequired}
for authentication failures. McpServerReadyState Server is running and serving requests. McpServerStartingState Server is registered with the host but has not yet started. McpServerStoppedState Server has been shut down. The host MAY remove the server from the
session entirely shortly after this state. Message A message that initiates or steers a turn. Messages can originate from the
user, the agent, a tool, or be system-generated (see {@link MessageOrigin}). MessageAnnotationsAttachment An attachment that references annotations on a session’s annotations
channel (see {@link AnnotationsState}). MessageEmbeddedResourceAttachment An attachment whose data is embedded inline as a base64 string. MessageOrigin Identifies the origin of a {@link Message} — who produced it. For the message
that initiates a turn ({@link Turn.message}), this is also the origin of the
turn; for steering or queued messages it is just the origin of that message. MessageResourceAttachment An attachment that references a resource by URI. The content is not
delivered inline; consumers can fetch it via resourceRead when needed. ModelSelection A model selection: the chosen model ID together with any model-specific
configuration values whose keys correspond to the model’s
{@link SessionModelInfo.configSchema}. MultipleChatsCapability Options for the {@link AgentCapabilities.multipleChats} capability. PendingMessage A message queued for future delivery to the agent. PluginCustomization An Open Plugins plugin. ProjectInfo Server-owned project metadata for a session. PromptCustomization A prompt contributed by a plugin or directory. ProtectedResourceMetadata Describes a protected resource’s authentication requirements using
RFC 9728 (OAuth 2.0
Protected Resource Metadata) semantics. ReasoningResponsePart Reasoning/thinking content from the model. ResourceChange A single change observed by a resource watcher. ResourceResponsePart A content part that’s a reference to large content stored outside the state tree. ResourceWatchState Full state for a single resource watch, returned when a client subscribes
to an ahp-resource-watch: URI. RootConfigState Live agent-host configuration metadata. RootState Global state shared with every client subscribed to ahp-root://. RuleCustomization A rule contributed by a plugin or directory. SessionActiveClient A client currently providing tools and interactive capabilities to a session. SessionChatInputRequest A user-input elicitation surfaced at the session level, mirroring one entry
of the owning chat’s {@link ChatState.inputRequests}. SessionConfigPropertySchema A session configuration property descriptor. SessionConfigSchema A JSON Schema object describing available session configuration metadata. SessionConfigState Live session configuration metadata. SessionModelInfo SessionState Full state for a single session, loaded when a client subscribes to the session’s URI. SessionStatus Bitset of summary-level session status flags. SessionSummary Lightweight catalog entry summarizing one session. Surfaced via
{@link RootChannelCommands.listSessions | root/listSessions} and
root/sessionAdded/root/sessionSummaryChanged notifications. SessionToolClientExecutionRequest A running tool whose execution is delegated to an active client. Surfaced so
a client that provides the tool can pick up the work without subscribing to
the owning chat. SessionToolConfirmationRequest A tool call blocked on confirmation — either parameter confirmation before
execution or result confirmation after — surfaced at the session level. SimpleMessageAttachment A simple, opaque attachment whose model representation is described by
the producer. SkillCustomization A skill contributed by a plugin or directory. Snapshot A point-in-time snapshot of a subscribed resource’s state, returned by
initialize, reconnect, and subscribe. SystemNotificationResponsePart A system notification surfaced as part of the response stream. TelemetryCapabilities OTLP telemetry channels the agent host emits. TerminalClientClaim A terminal claimed by a connected client. TerminalCommandPart A single command: its command line and the output it produced. TerminalInfo Lightweight terminal metadata exposed on the root state. TerminalSessionClaim A terminal claimed by a session, optionally scoped to a specific turn or tool call. TerminalState Full state for a single terminal, loaded when a client subscribes to the terminal’s URI. TerminalUnclassifiedPart Unstructured terminal output — content before, between, or after commands,
or from terminals that do not support command detection. TextPosition A zero-based position within a textual document. TextRange A range within a textual document. TextSelection A selection within a textual resource. ToolAnnotations Behavioral hints about a tool. All properties are advisory and not
guaranteed to faithfully describe tool behavior. ToolCallCancelledState Tool call was cancelled before execution. ToolCallClientContributor ToolCallCompletedState Tool completed successfully or with an error. ToolCallMcpContributor ToolCallPendingConfirmationState Parameters are complete, or a running tool requires re-confirmation
(e.g. a mid-execution permission check). ToolCallPendingResultConfirmationState Tool finished executing, waiting for client to approve the result. ToolCallResponsePart A tool call represented as a response part. ToolCallResult Tool execution result details, available after execution completes. ToolCallRunningState Tool is actively executing. ToolCallStreamingState LM is streaming the tool call parameters. ToolDefinition Describes a tool available in a session, provided by either the server or the active client. ToolResultEmbeddedResourceContent Base64-encoded binary content embedded in a tool result. ToolResultFileEditContent Describes a file modification performed by a tool. ToolResultResourceContent A reference to a resource stored outside the tool result. ToolResultSubagentContent A reference, embedded in a tool result, to a worker chat spawned by the tool
call (a sub-agent delegation), referenced by a chat URI (ahp-chat:/...). ToolResultTerminalCompleteContent Record of a command executed by a terminal-style tool (e.g. a shell tool),
appended to the tool result when the command exits. ToolResultTerminalContent A reference to a terminal whose output is relevant to this tool result. ToolResultTextContent Text content in a tool result. Turn A completed request/response cycle. UsageInfo ChangesetOperationScope Where a {@link ChangesetOperation} can be invoked. ChangesetOperationStatus Execution lifecycle of a {@link ChangesetOperation}. ChangesetStatus Computation lifecycle of a {@link ChangesetState}. ChatInputAnswer Draft, submitted, or skipped answer for one question. ChatInputAnswerState Answer lifecycle state. ChatInputAnswerValue Value captured for one answer. ChatInputAnswerValueKind Answer value kind. ChatInputQuestion One question within a chat input request. ChatInputQuestionKind Question/input control kind. ChatInputResponseKind How a client completed an input request. ChatInteractivity How a user can interact with a chat. ChatOrigin How a chat came into existence. ChatOriginKind Discriminant for {@link ChatOrigin} — how a chat came into existence. ChildCustomization A child customization living inside a plugin or directory. ConfirmationOptionKind Whether a confirmation option represents an approval or denial action. Customization A top-level customization (plugin, directory, or bare MCP server). CustomizationLoadState Host-reported load state for a container customization. CustomizationLoadStatus Discriminant values for {@link CustomizationLoadState}. CustomizationType Discriminant for the kind of customization. McpAuthRequiredReason Why an MCP server is currently in the {@link McpServerStatus.AuthRequired}
state. Mirrors the three failure modes defined by the
MCP authorization spec . McpServerState Discriminated lifecycle status of an MCP server customization. McpServerStatus Discriminant for the {@link McpServerState} union. MessageAttachment An attachment associated with a Message. MessageAttachmentKind Discriminant for {@link MessageAttachment} variants. MessageKind Discriminant for {@link MessageOrigin} — identifies who produced a message. PendingMessageKind Discriminant for pending message kinds. PolicyState Policy configuration state for a model. ResourceChangeType Discriminant for {@link ResourceChange.type}. ResponsePart A single part of a response stream (text, tool call, reasoning, content reference). ResponsePartKind Discriminant for response part types. SessionInputRequest One outstanding piece of input a session is blocked on, aggregated across all chats. SessionInputRequestKind Discriminant for the kinds of outstanding input a session can surface in
{@link SessionState.inputNeeded}. SessionLifecycle Session initialization state. SnapshotState The state payload of a snapshot — root, session, chat, terminal,
changeset, resource-watch, or annotations state. TerminalClaim Who currently holds a terminal. TerminalClaimKind Discriminant for terminal claim kinds. TerminalContentPart A content part within terminal output. ToolCallCancellationReason Why a tool call was cancelled. ToolCallConfirmationReason How a tool call was confirmed for execution. ToolCallConfirmationState A tool call blocked on parameter- or result-confirmation. ToolCallContributor Reference to the contributor of the tool being called. ToolCallContributorKind ToolCallState Full tool call lifecycle state. ToolCallStatus Status of a tool call in the lifecycle state machine. ToolResultContent Content block in a tool result. ToolResultContentType Discriminant for tool result content types. TurnState How a turn ended.